The five permanent members of the United Nations Security Council have reiterated a call for Iran to co-operate with the International Atomic Energy Agency (IAEA) over its nuclear programme.
The US, France, Russia, China and Britain also urged Tehran to grant inspectors access to its nuclear sites, in a statement released at a non-proliferation conference in Vienna.
The renewed call comes as the IAEA confirmed that the next round of talks with Iranian officials will take place on the 14th and 15th May.
Iran’s Deputy Foreign Minister has emphasised what he say is the country’s inalienable right to use peaceful nuclear technology.
But Mohammad Mahdi Akhondzadeh says Iran is optimistic about the upcoming talks.
Negotiations were called off earlier in the year after the IAEA complained it was denied access to a military site near Tehran, where explosives testing for warhead research had allegedly taken place.
The West alleges that Iran is trying to develop an atomic bomb, which Tehran denies.